Add close terminals context menu to terminal tabs

[SougandhS]

Right-clicking a terminal tab now shows a context menu with: Close, Close Others, Close Tabs to the Left/Right, and Close All.

Similar what editors tabs have in Eclipse

[github-actions]

Test Results

    51 files   -   3      51 suites   - 3   59m 11s ⏱️ + 1m 42s
 4 467 tests  - 383   4 445 ✅  - 383   22 💤 ±0  0 ❌ ±0 
11 490 runs   - 951  11 336 ✅  - 951  154 💤 ±0  0 ❌ ±0 

Results for commit 4caef14. ± Comparison against base commit d234c3a.

This pull request removes 383 tests.

org.eclipse.ua.tests.doc.internal.linkchecker.ApiDocTest ‑ testTopicsReference
org.eclipse.ua.tests.doc.internal.linkchecker.LinkTest ‑ testAllLinks
org.eclipse.ua.tests.doc.internal.linkchecker.TocLinkChecker ‑ testJdtIsvGenerated
org.eclipse.ua.tests.doc.internal.linkchecker.TocLinkChecker ‑ testJdtIsvStatic
org.eclipse.ua.tests.doc.internal.linkchecker.TocLinkChecker ‑ testJdtUser
org.eclipse.ua.tests.doc.internal.linkchecker.TocLinkChecker ‑ testPdeUserGenerated
org.eclipse.ua.tests.doc.internal.linkchecker.TocLinkChecker ‑ testPdeUserStatic
org.eclipse.ua.tests.doc.internal.linkchecker.TocLinkChecker ‑ testPlatformIsvGenerated
org.eclipse.ua.tests.doc.internal.linkchecker.TocLinkChecker ‑ testPlatformIsvStatic
org.eclipse.ua.tests.doc.internal.linkchecker.TocLinkChecker ‑ testPlatformUser
…

♻️ This comment has been updated with latest results.

[SougandhS]

Hi @laeubi, could you please check this PR when you get some time ?

[SougandhS]

Hi @merks, can you have a look at this PR when you get some time ?